Experimental study on the bond behavior between H-shaped steel and engineered cementitious composites

This paper investigated the bond behavior of H-shaped steel embedded in engineered cementitious composites (ECC). The specimens were designed and subjected to a push-out test. The key parameters researched were the volume fraction of polyvinyl alcohol (PVA) fiber, stirrup reinforcement ratio, ECC cover thickness and H-shaped steel embedded length. The tau-S curves at the loaded end were obtained, and the strain distributions of the web and flange steel along the embedded length were analyzed. The results showed that the critical bond stress increased with the volume fraction of PVA fiber and that increasing the ECC cover thickness can significantly enhance the ultimate bond stress and residual bond stress. However, the ultimate bond stress declined slightly when the embedded length was increased. The stirrup reinforced ratio had little influence on the critical bond stress. The H-shaped steel developed inelastic behavior at the loaded end when the ECC cover thickness reached 70 mm or the embedded length reached 600 mm. The bond stress had a non-uniform distribution depending on the strain of the H-shaped steel. The critical points were defined to establish a bond stress-slip model, and the theoretical model coincided with test results well. (C) 2018 Elsevier Ltd. All rights reserved.